Histopathologic Influences of Tissue Eosinophilia among Chronic Rhinosinusitis Patients

Background A subset of chronic rhinosinusitis (CRS) patients demonstrates tissue eosinophilia on structured histopathology. Prior studies have suggested that these patients are at increased risk for recurrent disease. The goals of this study are to identify histopathologic features of CRS patients with tissue eosinophilia and compare the influence of tissue eosinophilia to the effects of age and revision surgery on histopathology. Methods A structured histopathology report was utilized to analyze sinus tissue removed during functional endoscopic sinus surgery. Binomial logistic regression analysis was conducted to evaluate the association of age at diagnosis, tissue eosinophil count, and history of revision surgery with histopathology variables. Results A total of 281 CRS patients were included, of which 106 had tissue eosinophilia. Regression analysis demonstrated that tissue eosinophilia was associated with degree of inflammation (odds ratio [OR] 5.744; P < .001), neutrophilic infiltrate (OR 1.882; P = .020), basement membrane thickening (OR 3.561; P < .001), squamous metaplasia (OR 3.315; P < .001), fibrosis (OR 2.246; P = .002), presence of Charcot–Leyden crystals (OR 20.700; P = .004), and eosinophilic aggregates (OR 34.172; P < .001). Age and history of revision surgery were not significant predictors of histopathology variables on multivariate analysis. Conclusion Tissue eosinophilia appears to be the predominant driving factor of histopathologic changes irrespective of previous sinus surgery or age at diagnosis. These findings may have important implications for postsurgical management and prognosis for patients with tissue eosinophilia presenting for revision surgery.